EXAM 1 GEOLOGY

What is the difference between weather and climate?

Climate is the long-term average of daily weather conditions.

What are Koppen Climate Zones?

A climate classification system that divides the Earth into different climate regions based on temperature, precipitation, and vegetation patterns.

What are three recently observed climate-related trends?

Glacial melting, surface temperature increase, and sea level rise.

What are sediment cores and what do they reveal?

Sediment cores are samples taken from ocean floors or lake beds that contain evidence of past climate conditions, including elements and isotopes that help reconstruct historical climate patterns.

What are natural causes of climate change?

Changes in positions/shapes of landmasses, blocking of incoming solar radiation, changes in solar energy (sun spots), and Milankovitch cycles.

What is the Milankovitch Theory?

Theory stating that climate variations are predicted by cyclical changes in Earth's orbital geometry, including eccentricity, obliquity, and precession.

What is insolation?

Solar radiation energy received on a given surface in a given time.

What is anthropogenic climate change?

Climate change caused by human activities, particularly greenhouse gas emissions.

What are the four main components of the Earth system?

Geosphere, atmosphere, hydrosphere, and biosphere.

What is the carbon cycle?

The process by which carbon moves between different Earth system components (atmosphere, oceans, land, organisms).

What is the greenhouse effect?

The process where short wavelength solar radiation reaches Earth, while long wavelength terrestrial radiation is absorbed and reemitted by greenhouse gases, warming the planet.

Why is the greenhouse effect necessary?

It's necessary for life on Earth as we know it by maintaining temperatures suitable for life.

What are examples of greenhouse gases?

Carbon dioxide, methane, and water vapor.

What is a Global Climate Model/General Circulation Model?

Mathematical models that use equations to represent Earth processes to predict changes that may occur with changing inputs.

What are Representative Concentration Pathways (RCPs) in IPCC reports?

Different greenhouse gas concentration scenarios used to model possible climate futures.

What changes in precipitation are projected due to climate change?

Overall precipitation increase, changing precipitation patterns, and more droughts and flooding.

What is projected to happen with sea levels according to climate models?

Sea levels are projected to rise relative to a 1985-2005 baseline.

What are the main goals of the Paris Agreement (2016)?

Keep global temperature rise this century below 2 degrees Celsius above pre-industrial levels.

What are examples of proposals to minimize carbon emissions?

Raising taxes on electricity/gasoline, tax breaks for nuclear power, and tax breaks for renewable energy.

What are examples of actions that can reduce an individual's carbon footprint?

Replacing incandescent light bulbs with energy-efficient ones, washing clothes in cold water, and reducing meat consumption.

What is geoengineering?

Large-scale technological interventions in Earth's climate system to counteract climate change.

What does George E.P. Box say about models?

"All models are wrong, but some are useful."

What are the three main stages in forming the universe?

The Big Bang, light element formation, and the forming of galaxies and stars.

How did the solar system and Earth form?

From an initial nebula of gas and space dust that contracted due to gravity.

What are the key differences between inner and outer planets?

Inner planets are less massive, denser, and smaller than outer planets.

What are the three main chemical layers of Earth's interior?

The crust, the mantle, and the core.

What are the two types of crust and how do they differ?

Continental crust is thicker and less dense, while oceanic crust is thinner and more dense.

What is the composition of the mantle?

Ultramafic (iron and magnesium-rich) rock, primarily peridotite.

What are the key characteristics of Earth's core?

An iron-rich sphere; the outer core is liquid while the inner core is solid.

What is a lithospheric plate?

The rigid outer layer of Earth consisting of the crust and upper mantle.

What are the three main types of plate boundaries?

Divergent, convergent, and transform boundaries.

What happens at divergent plate boundaries?

Plates move apart, creating rift valleys or mid-ocean ridges.

What are the three types of convergent boundaries?

Continent-continent collision, ocean-ocean convergence, and continent-ocean convergence.

What are transform boundaries characterized by?

Shear zones between plates with little mountain building or volcanic activity.

Who was Alfred Wegener and what theory did he propose?

A German meteorologist who proposed Continental Drift.

What evidence did Wegener use to support Continental Drift?

Matching geologic structures across continents, fossil localities, and evidence of ancient climates.

Why was Continental Drift initially rejected?

Wegener couldn't explain the driving force behind it.

What ocean floor observations helped develop the theory of plate tectonics?

Echo sounding measurements and discoveries of the global mid-ocean ridge.

What is paleomagnetism?

Natural remnant magnetism in rocks that shows magnetic reversals.

What is sea floor spreading and who proposed it?

The theory that new seafloor is produced between diverging plates, proposed by Hess in 1960.

How do magnetic 'stripes' on the ocean floor relate to plate tectonics?

Magnetic polarity reversals are imprinted in sea-floor rock.

What modern evidence supports plate tectonic theory?

Earthquake and volcano locations, direct GPS measurements of plate movement.

What are the potential driving mechanisms for plate tectonics?

Convection in the mantle, ridge push, and slab pull.

What are the five characteristics of minerals?

Naturally occurring, solid, crystalline structure, definite chemical composition, mostly inorganic.

What are five ways minerals can form?

Solidification from a melt, precipitation from a solution, solid-state diffusion, biomineralization, and from gas.

What are three ways minerals can be destroyed?

Melting, dissolving, and chemical reactions.

What physical properties are used to identify minerals in hand samples?

Crystal form, luster, color, streak, hardness, cleavage, and fracture.

What is mineral hardness and how is it measured?

Resistance to being scratched, measured on the Mohs scale.

What is the difference between cleavage and fracture?

Cleavage is the tendency to break along planes of weak bonding; fracture is breaking that's not along cleavage planes.

What are two advanced methods of mineral identification?

Optical mineralogy and X-ray techniques.

How are minerals classified?

By the anion or anion complex they contain.

What is a rock?

An aggregate of one or more minerals.

What are the three main rock types and how do they form?

Igneous, sedimentary, and metamorphic.

What is the difference between magma and lava?

Magma is melted rock below the ground, while lava is above ground.

What are the sources of Earth's internal heat?

Remnant heat and ongoing heat generation.

What is the geothermal gradient?

The increase in temperature with depth in the Earth.

How does decompression melting work?

Pressure decreases while the base of the crust is hot enough to melt mantle rock.

How does water contribute to melting in the mantle?

Water under high pressure breaks silicon-oxygen bonds, liquefying at lower temperatures.

What is a glacier?

A mass of ice that moves over land due to its own weight.

Where do glaciers form?

Where more snow falls in winter than melts in summer.

What are the two main types of glaciers?

Mountain (Alpine) Glaciers and Continental Glaciers.

How do glaciers move?

Plastic Flow and Basal Slip.

What is the glacial budget?

The balance between accumulation and ablation.

What are some erosional features created by glaciers?

Cirque, Horn, Arete, and U-Shaped Valley.

What are the different types of glacial deposition?

Till, Moraines, and Outwash Plains.

What is Bowen’s Reaction Series?

A sequence explaining the order of mineral crystallization and melting.

What are the two main igneous environments?

Intrusive and Extrusive.

How does cooling rate affect igneous rock texture?

Slow cooling leads to large crystals, fast cooling leads to small crystals.

What is a volcano?

A vent in the Earth's crust where molten rock and gases erupt.

What are the three main types of volcanoes?

Shield Volcanoes, Cinder Cones, and Stratovolcanoes.

What are the two main eruptive styles?

Effusive and Explosive.

What volcanic hazards exist?

Lava flows, pyroclastic flows, tephra, lahars, and gases.

How do scientists monitor volcanoes?

Through seismic activity, heat flow, gas emissions, and ground deformation.

What is the Volcanic Explosivity Index (VEI)?

A scale measuring eruption size based on ejected material volume.

How can volcanic hazards be mitigated?

Through evacuation and lava flow diversion.

What are glacial consequences related to sea levels?

More ice leads to lower sea level, less ice leads to higher sea level.

What is partial melting?

Magma is usually more felsic than the original rock due to low-melting minerals melting first.

What are the main components of the crust, mantle, and core?

Crust: O, Si, Al, Fe, Mg; Mantle: Mg, Fe, Si; Core: Fe, Ni.

What is the difference between intrusive and extrusive rocks?

Intrusive rocks have large crystals while extrusive rocks have small crystals.

What is a caldera?

A large volcanic depression formed when a magma chamber empties and collapses.

What are pahoehoe and a’a’ lava types?

Pahoehoe is smooth, ropy lava; a’a’ is jagged, blocky lava.

How do volcanic gases affect climate?

SO₂ aerosol formation blocks sunlight; CO₂ contributes to greenhouse warming.